// Emacs style mode select   -*- C++ -*-
//-----------------------------------------------------------------------------
//
// Copyright (C) 1993-1996 by id Software, Inc.
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU General Public License
// as published by the Free Software Foundation; either version 2
// of the License, or (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// DESCRIPTION:
//      Refresh/rendering module, shared data struct definitions.
//
//-----------------------------------------------------------------------------

#ifndef __R_DEFS__
#define __R_DEFS__

// Screenwidth.
#include "doomdef.h"

// Some more or less basic data types
// we depend on.
#include "m_fixed.h"

// We rely on the thinker data struct
// to handle sound origins in sectors.
#include "d_think.h"
// SECTORS do store MObjs anyway.
#include "p_mobj.h"

// Silhouette, needed for clipping Segs (mainly)
// and sprites representing things.
#define SIL_NONE                0
#define SIL_BOTTOM              1
#define SIL_TOP                 2
#define SIL_BOTH                3

#define MAXDRAWSEGS             256

//
// INTERNAL MAP TYPES
//  used by play and refresh
//

//
// Your plain vanilla vertex.
// Note: transformed values not buffered locally,
//  like some DOOM-alikes ("wt", "WebView") did.
//
typedef struct
{
    fixed_t     x;
    fixed_t     y;

} vertex_t;

// Forward of LineDefs, for Sectors.
struct line_s;

// Each sector has a degenmobj_t in its center
//  for sound origin purposes.
// I suppose this does not handle sound from
//  moving objects (doppler), because
//  position is prolly just buffered, not
//  updated.
typedef struct
{
    thinker_t           thinker;        // not used for anything
    fixed_t             x;
    fixed_t             y;
    fixed_t             z;

} degenmobj_t;

//
// The SECTORS record, at runtime.
// Stores things/mobjs.
//
typedef struct
{
    fixed_t     floorheight;
    fixed_t     ceilingheight;
    short       floorpic;
    short       ceilingpic;
    short       lightlevel;
    short       special;
    short       tag;

    // 0 = untraversed, 1,2 = sndlines -1
    int         soundtraversed;

    // thing that made a sound (or null)
    mobj_t*     soundtarget;

    // mapblock bounding box for height changes
    int         blockbox[4];

    // origin for any sounds played by the sector
    degenmobj_t soundorg;

    // if == validcount, already checked
    int         validcount;

    // list of mobjs in sector
    mobj_t*     thinglist;

    // thinker_t for reversable actions
    void*       specialdata;

    int                 linecount;
    struct line_s**     lines;  // [linecount] size

} sector_t;

//
// The SideDef.
//

typedef struct
{
    // add this to the calculated texture column
    fixed_t     textureoffset;

    // add this to the calculated texture top
    fixed_t     rowoffset;

    // Texture indices.
    // We do not maintain names here.
    short       toptexture;
    short       bottomtexture;
    short       midtexture;

    // Sector the SideDef is facing.
    sector_t*   sector;

} side_t;

//
// Move clipping aid for LineDefs.
//
typedef enum
{
    ST_HORIZONTAL,
    ST_VERTICAL,
    ST_POSITIVE,
    ST_NEGATIVE

} slopetype_t;

typedef struct line_s
{
    // Vertices, from v1 to v2.
    vertex_t*   v1;
    vertex_t*   v2;

    // Precalculated v2 - v1 for side checking.
    fixed_t     dx;
    fixed_t     dy;

    // Animation related.
    short       flags;
    short       special;
    short       tag;

    // Visual appearance: SideDefs.
    //  sidenum[1] will be -1 if one sided
    short       sidenum[2];

    // Neat. Another bounding box, for the extent
    //  of the LineDef.
    fixed_t     bbox[4];

    // To aid move clipping.
    slopetype_t slopetype;

    // Front and back sector.
    // Note: redundant? Can be retrieved from SideDefs.
    sector_t*   frontsector;
    sector_t*   backsector;

    // if == validcount, already checked
    int         validcount;

    // thinker_t for reversable actions
    void*       specialdata;
} line_t;

//
// A SubSector.
// References a Sector.
// Basically, this is a list of LineSegs,
//  indicating the visible walls that define
//  (all or some) sides of a convex BSP leaf.
//
typedef struct subsector_s
{
    sector_t*   sector;
    short       numlines;
    short       firstline;

} subsector_t;

//
// The LineSeg.
//
typedef struct
{
    vertex_t*   v1;
    vertex_t*   v2;

    fixed_t     offset;

    angle_t     angle;

    side_t*     sidedef;
    line_t*     linedef;

    // Sector references.
    // Could be retrieved from linedef, too.
    // backsector is NULL for one sided lines
    sector_t*   frontsector;
    sector_t*   backsector;

} seg_t;

//
// BSP node.
//
typedef struct
{
    // Partition line.
    fixed_t     x;
    fixed_t     y;
    fixed_t     dx;
    fixed_t     dy;

    // Bounding box for each child.
    fixed_t     bbox[2][4];

    // If NF_SUBSECTOR its a subsector.
    unsigned short children[2];

} node_t;

// posts are runs of non masked source pixels
typedef struct
{
    byte                topdelta;       // -1 is the last post in a column
    byte                length;         // length data bytes follows
} post_t;

// column_t is a list of 0 or more post_t, (byte)-1 terminated
typedef post_t  column_t;

//
// OTHER TYPES
//

// This could be wider for >8 bit display.
// Indeed, true color support is posibble
//  precalculating 24bpp lightmap/colormap LUT.
//  from darkening PLAYPAL to all black.
// Could even us emore than 32 levels.
typedef byte    lighttable_t;

//
// ?
//
typedef struct drawseg_s
{
    seg_t*              curline;
    int                 x1;
    int                 x2;

    fixed_t             scale1;
    fixed_t             scale2;
    fixed_t             scalestep;

    // 0=none, 1=bottom, 2=top, 3=both
    int                 silhouette;

    // do not clip sprites above this
    fixed_t             bsilheight;

    // do not clip sprites below this
    fixed_t             tsilheight;

    // Pointers to lists for sprite clipping,
    //  all three adjusted so [x1] is first value.
    short*              sprtopclip;
    short*              sprbottomclip;
    short*              maskedtexturecol;

} drawseg_t;

// Patches.
// A patch holds one or more columns.
// Patches are used for sprites and all masked pictures,
// and we compose textures from the TEXTURE1/2 lists
// of patches.
typedef struct
{
    short               width;          // bounding box size
    short               height;
    short               leftoffset;     // pixels to the left of origin
    short               topoffset;      // pixels below the origin
    int                 columnofs[8];   // only [width] used
    // the [0] is &columnofs[width]
} patch_t;

// A vissprite_t is a thing
//  that will be drawn during a refresh.
// I.e. a sprite object that is partly visible.
typedef struct vissprite_s
{
    // Doubly linked list.
    struct vissprite_s* prev;
    struct vissprite_s* next;

    int                 x1;
    int                 x2;

    // for line side calculation
    fixed_t             gx;
    fixed_t             gy;

    // global bottom / top for silhouette clipping
    fixed_t             gz;
    fixed_t             gzt;

    // horizontal position of x1
    fixed_t             startfrac;

    fixed_t             scale;

    // negative if flipped
    fixed_t             xiscale;

    fixed_t             texturemid;
    int                 patch;

    // for color translation and shadow draw,
    //  maxbright frames as well
    lighttable_t*       colormap;

    int                 mobjflags;

} vissprite_t;

//
// Sprites are patches with a special naming convention
//  so they can be recognized by R_InitSprites.
// The base name is NNNNFx or NNNNFxFx, with
//  x indicating the rotation, x = 0, 1-7.
// The sprite and frame specified by a thing_t
//  is range checked at run time.
// A sprite is a patch_t that is assumed to represent
//  a three dimensional object and may have multiple
//  rotations pre drawn.
// Horizontal flipping is used to save space,
//  thus NNNNF2F5 defines a mirrored patch.
// Some sprites will only have one picture used
// for all views: NNNNF0
//
typedef struct
{
    // If false use 0 for any position.
    // Note: as eight entries are available,
    //  we might as well insert the same name eight times.
    boolean     rotate;

    // Lump to use for view angles 0-7.
    short       lump[8];

    // Flip bit (1 = flip) to use for view angles 0-7.
    byte        flip[8];

} spriteframe_t;

//
// A sprite definition:
//  a number of animation frames.
//
typedef struct
{
    int                 numframes;
    spriteframe_t*      spriteframes;

} spritedef_t;

//
// Now what is a visplane, anyway?
//
typedef struct
{
  fixed_t               height;
  int                   picnum;
  int                   lightlevel;
  int                   minx;
  int                   maxx;

  // leave pads for [minx-1]/[maxx+1]

  unsigned short pad1;
  // Here lies the rub for all
  //  dynamic resize/change of resolution.
  unsigned short top[SCREENWIDTH];
  unsigned short pad2;
  unsigned short pad3;
  // See above.
  unsigned short bottom[SCREENWIDTH];
  unsigned short pad4;

} visplane_t;

#endif  // __R_DEFS__
